Most vehicles, in particular electric and hybrid vehicles, include power systems usually referred to as battery management systems (BMSs) that monitor and control the operation of the batteries within the vehicles. For example, the BMS of an electric vehicle controls the vehicle's powertrain as well as auxiliary components or features, such as heating and cooling components, dashboard electronics, etc. Many electric vehicles utilize a high capacity, high voltage battery to drive the vehicle's powertrain and utilize a lower capacity and lower voltage battery for the auxiliary components. However, as the industry continues to add auxiliary features to vehicles, additional/alternative power systems are desired.